1. Field of the Invention
The invention relates to a modulation device for use in a charged particle multi-beamlet lithography system. The invention further relates to a charged-particle multi-beamlet lithography system.
2. Description of the Related Art
Charged particle multi-beamlet systems are known, for example from U.S. Pat. No. 6,958,804. The system described in this patent preferably uses a plurality of electron beamlets to transfer a pattern to a target surface. The electron beamlets generated by a radiation source are modulated in a modulation device by electrostatic deflection in accordance with pattern data. The modulated beamlets are then transferred to the target surface. To enable high speed transfer of the pattern to the target surface, the pattern data for controlling the electrostatic deflection are transferred at least partly using optical transmission using modulated light beams.